Node.js Express CLAUDE.md Template

# Express.js Project

## Overview
Node.js REST API built with Express framework.

## Tech Stack
- Runtime: Node.js 20+
- Framework: Express 4.x
- Language: JavaScript/TypeScript
- Database: PostgreSQL/MongoDB
- ORM: Prisma/Mongoose

## Key Commands
```bash
npm run dev       # Start with nodemon
npm start         # Production start
npm test          # Run Jest tests
npm run lint      # ESLint check
npm run build     # TypeScript build
```

## Project Structure
```
src/
├── index.js          # Entry point
├── app.js            # Express app setup
├── routes/           # Route definitions
├── controllers/      # Request handlers
├── middleware/       # Custom middleware
├── models/           # Database models
├── services/         # Business logic
├── utils/            # Helper functions
└── config/           # Configuration
```

## Conventions
- Use async/await, not callbacks
- Centralized error handling middleware
- Validate request bodies with Joi/Zod
- Use environment variables for config

## Important Notes
- Error handler must be last middleware
- Use helmet for security headers
- Rate limiting on public endpoints